Biology 2- Animal Science 1.1

traits shared by all animals

multicellular, eukaryotic, heterotrophic ingestive, lacking cell walls, have nuclei, move during at least one stage of life

domain and kingdom of animals

domain eukarya, kingdom animalia

nine major phyla of animals

porifera, cnidaria, platyhelminthes, nematodes, annelids, mollusca, arthropoda, echinoderms, chordates

the two major trends in animal evolution

increase in locomotion ability and size

what are the important morphological features used to classify

tissues, body systems, body symmetry, cephalization, body cavity, development

tissues

groups of similar cells conducting same function

diploblasts and triploblasts

diploblastic animals have two germ layers (ectoderm and endoderm) while triploblastic have three (+ mesoderm)

ectoderm

outermost layer of cells or tissue in embryo, form skin and nervous systems

endoderm

innermost layer of cells or tissue in embryo, form lining of digestive tract; can also be called gastrodermis

mesoderm

middle layer of cells or tissue in embryo, forms circulatory, muscular, bone, and organ tissues

what is a common trait of triploblasts

more complex than diploblasts

coelom

body cavity which contains fluid, digestive tract and organs

why are sponges unique

lack tissues, neurons, muscles, and other complex structure

central nervous system

clusters of neurons, organized, associated with bilateral symmetry

nerve net

nervous system not organized or centralized, only cnidarians, associated with radial symmetry

cephalization

concentration of sensory, processing, and feeding structures

acoelomates and pseudocoelomates

no cavity, false coelom not fully lined by mesoderm, lighter and more flexible than acoelomate, less supportive than full coelom

protostomes

pore in development becomes mouth

deuterostomes

pore in development becomes anus

both protostomes and deuterostomes

produce bilaterally symmetrical results with coeloms

complete vs incomplete digestive tracts

complete has two openings (mouth and exit) while incomplete has only one that does both jobs

segmentation 

body cavity divides into segments, allows for specialization of regions, more effective locomotion

cephalization

evolutionary event, development of senses

feeding methods

filter suspension (baleen whale), deposit (worms), fluid (butterfly), mass (people)

four food source types

herbivores, carnivores, omnivores, detritovores

endo vs ecto parasites

endo live in, ecto live on

cilia, flagella, and other appendages allow for

movement

three egg development types

oviparous (egg bearing like birds), viviparous (live bearing like deer), ovoviviparous (egg live mix like sharks)

complete vs incomplete metamorphosis

both are changes in form during life cycle, incomplete (hemimetabolous) has “half change” nymph and adult and both life forms feed on same material, complete (holometabolous) has “whole change” with pupa stage and specialized feeding between stages

why is complete metamorphosis common and better

reduces competition for adults and young of the species

definitive host vs intermediate host

organism reproduces sexually, vs asexually

protostome animals (features, pore, cleavage, cell fates)

bilateral coelomates, mouth pore, spiral cleavage pattern instead of radial, determinate cell fates instead of indeterminate

two major groups of protostome animals

lophotrochozoans (don’t molt exoskeleton, includes mollusks) and ecdysozoa (grow by molting, includes arthropods)

lophotrochozoans two subtypes

lophotrochozoans (suspension feeding and still) and trochophores (swim and feed)

mantle

epidermal layer that secretes shell

ossicles

endoskeletal calcium plates

echinodermatal water vascular system

radiates from central ring canal, five radial canals, water enters through madreporite, hollow tube feet and ampulla bases, function is operating tube feet by letting water pump 

notochord and other structures

spine like structure in chordates, alongside dorsal hollow nerve chord, postanal tail and pharyngeal slits